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Pin Voltage Charts

To read values requires the use of a OBD-II scan tool, DVOM, Breakout Box (981-3190 ) and Adapter (951-1351 ). Manufacturer does not recommend checking values directly at ECM connectors, as damage to wiring harness or ECM harness connector could occur. Unless otherwise specified, values specified in table are with ignition on and engine at normal operating temperature. Unless otherwise specified, use terminal A42 for ground if testing ECM "A" connector or terminal B28 for ground if testing ECM "B" connector.

ELECTRONIC CONTROL MODULE (ECM) PIN VALUES (C70, S70 & V70 MOTRONIC 4.4)

ECM Terminal (1) Circuit (Condition) Voltage
A1 N/A N/A
A2 Front Knock Sensor (Ignition On) Zero
A3 Mass Airflow Sensor Power Ground (Ignition On) Zero
A4 Mass Airflow Sensor Signal (Ignition On) .1-.2
" Mass Airflow Sensor Signal (Engine Idling) .9
A5 Mass Airflow Sensor Signal Ground (Ignition On) Zero
A6 RPM Sensor Signal Ground (Ignition On) Zero
A7 Low Speed Cooling Fan (Fan Off) Battery
" Low Speed Cooling Fan (Fan On) Less Than 0.1
A8 N/A N/A
A9 Injector No. 5 (Ignition On) Battery
" Injector No. 5 (Engine Idling) (2)
A10 Injector No. 1 (Ignition On) Battery
" Injector No. 1 (Engine Idling) (2)
A11 Idle Air Control Valve Opening Signal (Ignition On) (3)
" Idle Air Control Valve Opening Signal (Engine Idling) (4)
A12 Power Supply (Ignition On) Battery
A13 Power Ground (Ignition On) Zero
A14 Front Oxygen Sensor Heating Signal (Ignition On) Battery
A15 Throttle Position Sensor Power (Ignition On) 4.8
A16 Throttle Position Sensor Signal (Ignition On & Closed Throttle) 0.5
" Throttle Position Sensor Signal (Ignition On & Wide Open Throttle) 4.3
A17 Front & Rear Knock Sensor Negative Signal (Ignition On) Zero
A18 Sensor Ground Signal (Ignition On) Zero
A19 Rear Heated Oxygen Sensor (Ignition On) 0.7
A20 RPM Sensor Signal (Ignition On) Zero
" RPM Sensor Signal (Engine Idling) (5) 1.6
A21 Camshaft Position Sensor Signal (Ignition On) Zero Or 5
A22 High Speed Cooling Fan (Fan Off) Battery
" High Speed Cooling Fan (Fan On) Less Than 0.3
A23 Injector No. 4 (Ignition On) Battery
" Injector No. 4 (Engine Idling) (2)
A24 Injector No. 3 (Ignition On) Battery
" Injector No. 3 (Engine Idling) (2)
A25 Idle Air Control Valve Closing Signal (Ignition On) (6)
" Idle Air Control Valve Closing Signal (Engine Idling) (7)
A26 Power Supply From Battery (Ignition On) Battery
A27 Power Supply From Main Relay (Ignition On) Battery
A28 ECM Power Ground (Ignition On) Zero
A29 Rear Heated Oxygen Sensor Control Signal (Ignition On) Battery
A30 Rear Knock Sensor Positive Signal (Ignition On) Zero
A31 Engine Coolant Temperature Sensor Signal (Ignition On) (8)
A32 Front Heated Oxygen Sensor Positive Signal (Ignition On) (9) 1.1-1.2
" Front Heated Oxygen Sensor Positive Signal (Engine Idling) 0-0.9 (Fluctuates)
A33 Front Heated Oxygen Sensor Negative Signal (Ignition On) 0.7
A34 Rear Heated Oxygen Sensor Positive Signal (Ignition On) (9) Zero
A35 Outside Temperature Sensor 4.9
A36 Camshaft Position Sensor Power Supply (Ignition On) Battery
A37 PAIR Pump Valve Control Signal Battery
A38 Injector No. 2 (Ignition On) Battery
" Injector No. 2 (Engine Idling) (2)
A39 CP Valve Control Signal (Ignition On) Battery
" CP Valve Control Signal (Engine Idling) (10)
A40 N/A N/A
A41 Main Relay Control Signal (Ignition On) Zero
A42 ECM Signal Ground (Ignition On) (11) Zero
A43 N/A N/A
B1 Accelerometer Sensor Power Supply (Ignition On) 5
B2 Torque Reduction Signal From Transmission Control Module (Ignition On) 10-11 Volts
B3 Torque Reduction Signal From Transmission Control Module (Ignition On) 10-11 Volts
B4 Torque Reduction Signal To Transmission Control Module (Ignition On) 10 Volts
B5 N/A N/A
B6 A/C Compressor Status Signal (Ignition On) Zero
B7 Malfunction Indicator Light Control Signal (MIL On) 0.8
" Malfunction Indicator Light Control Signal (MIL Off) Battery
B8 N/A N/A
B9 A/C Pressure Sensor Signal (Ignition On) 0.9
B10 N/A N/A
B11 Power Stage Control Signal (Ignition On) 0.1
B12 Load Signal To Transmission Control Module (Ignition On) 0.8
B13-B14 N/A N/A
B15 Fuel Tank Pressure Sensor 5
B16-B17 N/A N/A
B18 Vehicle Speed Sensor Signal (Ignition On & Drive Wheel Turning) Zero Or Battery (Fluctuates)
B19 EVAP Canister Shut-Off Valve Battery
B20 Throttle Position Sensor Signal (Ignition On & Closed Throttle) 0.5
" Throttle Position Sensor Signal (Ignition On & Wide Open Throttle) 4.3
B21 Tachometer Signal (Ignition On) Battery
B22 Atmospheric Pressure Sensor 4.6
B23 Engine Coolant Temperature Sensor Signal (Ignition On & Closed Throttle) (12)
B24 PNP Idle Compensation Signal (Ignition On, In Park Or Neutral) Battery
" PNP Idle Compensation Signal (Ignition On, Except In Park Or Neutral) Zero
B25 A/C Relay Status Signal (Ignition On) Zero
B26 Malfunction Indicator Light Operation Request Signal (Ignition On) 0-1
B27 Fuel Pump Control Signal (Ignition On) 7.5
B28 Sensor Signal Ground (Ignition On) Zero
B29 A/C Pressure Sensor Power Supply (Ignition On) 5
B30 N/A N/A
B31 Fuel Tank Pressure Sensor 4.7-.6
B32 Accelerometer Sensor Signal (Ignition On) 2.5
B33-B35 N/A N/A
B36 Diagnostic Test Lead (Ignition On) 1-2 Volts Less Than Battery
B37 N/A N/A
B38 PAIR Pump Relay Control Relay Battery
B39 Fuel Consumption Signal (Ignition On) 10
B40 A/C Relay Control Signal (Ignition On) 9
B41 TC Control Valve Control Signal 12
B42 TC Boost Pressure Limiting Signal N/A
B43 N/A N/A
(1) Check pin value between specified terminal and ECM terminal A42 (ground) if testing ECM "A" connector, or terminal B28 (ground) if testing ECM "B" connector.
(2) Injector ON time is 2.2-3.6 milliseconds. ON time increases with engine speed and load.
(3) 26 percent duty cycle. Duty cycle increases with engine load.
(4) Specification is 21-32 percent duty cycle. Duty cycle increases with engine speed and load.
(5) A/C voltage.
(6) Specification is 75 percent duty cycle.
(7) Specification is 68-78 percent duty cycle. Duty cycle increases with engine speed and load.
(8) Voltage is 1.8 volts with sensor temperature at 68°F (20°C) or 1.9 volt with sensor temperature at 212°F (100°C).
(9) Measured with negative lead connected to terminal A19.
(10) Zero-33 percent duty cycle.
(11) Measured with negative lead connected to negative battery terminal.
(12) Specification is measured in Hertz (Hz). Specification is 40 Hz with sensor temperature at 68°F (20°C) or 21.2 Hz with sensor temperature at 212°F (100°C).
ELECTRONIC CONTROL MODULE (ECM) PIN VALUES (S90 & V90 MOTRONIC 4.4)

ECM Terminal (1) Circuit (Condition) Voltage
A1 N/A N/A
A2 Front Knock Sensor (Ignition On) Zero
A3 Mass Airflow Sensor Power Ground (Ignition On) Zero
A4 Mass Airflow Sensor Signal (Ignition On) .1-.2
" Mass Airflow Sensor Signal (Engine Idling) .1
A5 Mass Airflow Sensor Signal Ground (Ignition On) Zero
A6 RPM Sensor Signal Ground (Ignition On) Zero
A7 Low Speed Cooling Fan (Fan Off) Battery
" Low Speed Cooling Fan (Fan On) Less Than 0.3
A8 N/A N/A
A9 Injector No. 6 (Ignition On) Battery
" Injector No. 6 (Engine Idling) (2)
A10 Injector No. 1 (Ignition On) Battery
" Injector No. 1 (Engine Idling) (2)
A11 Idle Air Control Valve Opening Signal (Ignition On) (3)
" Idle Air Control Valve Opening Signal (Engine Idling) (4)
A12 Power Supply (Ignition On) Battery
A13 Power Ground (Ignition On) Zero
A14 Front Oxygen Sensor Heating Signal (Ignition On) Battery
A15 Throttle Position Sensor Power (Ignition On) 4.8
A16 Throttle Position Sensor Signal (Ignition On & Closed Throttle) 0.5
" Throttle Position Sensor Signal (Ignition On & Wide Open Throttle) 4.5
A17 Front & Rear Knock Sensor Negative Signal (Ignition On) Zero
A18 Sensor Ground Signal (Ignition On) Zero
A19 Rear Heated Oxygen Sensor (Ignition On) 0.7
A20 RPM Sensor Signal (Ignition On) Zero
" RPM Sensor Signal (Engine Idling) (5) 1.8
A21 Camshaft Position Sensor Signal (Ignition On) Zero Or 12
A22 High Speed Cooling Fan (Fan Off) Battery
" High Speed Cooling Fan (Fan On) Less Than 0.1
A23 Injector No. 3 (Ignition On) Battery
" Injector No. 3 (Engine Idling) (2)
A24 Injector No. 2 (Ignition On) Battery
" Injector No. 2 (Engine Idling) (2)
A25 Idle Air Control Valve Closing Signal (Ignition On) (6)
" Idle Air Control Valve Closing Signal (Engine Idling) (7)
A26 Power Supply From Battery (Ignition On) Battery
A27 Power Supply From Main Relay (Ignition On) Battery
A28 ECM Power Ground (Ignition On) Zero
A29 Rear Heated Oxygen Sensor Control Signal (Ignition On) Battery
A30 Rear Knock Sensor Positive Signal (Ignition On) Zero
A31 Engine Coolant Temperature Sensor Signal (Ignition On) (8)
A32 Front Heated Oxygen Sensor Positive Signal (Ignition On) (9) 1.1-1.2
" Front Heated Oxygen Sensor Positive Signal (Engine Idling) 0-0.9 (Fluctuates)
A33 Front Heated Oxygen Sensor Negative Signal (Ignition On) 0.7
A34 Rear Heated Oxygen Sensor Positive Signal (Ignition On) (9) 1.18
A35 Outside Temperature Sensor 4.9
A36 Camshaft Position Sensor Power Supply (Ignition On) Battery
A37 PAIR Pump Valve Control Signal Battery
A38 Injector No. 5 (Ignition On) Battery
" Injector No. 5 (Engine Idling) (2)
A39 CP Valve Control Signal (Ignition On) Battery
" CP Valve Control Signal (Engine Idling) (10)
A40 Fuel Pump Control Signal (Ignition On) Battery
" Fuel Pump Control Signal (Engine Idling) Zero
A41 Main Relay Control Signal (Ignition On) 1
A42 ECM Signal Ground (Ignition On) (11) Zero
A43 Injector No. 4 (Ignition On) Battery
" Injector No. 4 (Engine Idling) (2)
B1 Accelerometer Sensor Power Supply (Ignition On) 5
B2 Torque Reduction Signal From Transmission Control Module (Ignition On) 10-11 Volts
B3 Torque Reduction Signal From Transmission Control Module (Ignition On) 10-11 Volts
B4 Torque Reduction Signal To Transmission Control Module (Ignition On) 10 Volts
B5 N/A N/A
B6 A/C Compressor Status (Ignition On) Zero
" A/C Compressor Status (A/C On/Engine Idling) Battery
B7 Malfunction Indicator Light Control Signal (MIL On) 0.8
" Malfunction Indicator Light Control Signal (MIL Off) Battery
B8 N/A N/A
B9 A/C Pressure Sensor Signal (Ignition On) (13)
B10 Ignition Coil Cyl. No. 5 .1
B11 Ignition Coil Cyl. No. 1 .1
B12 Load Signal To Transmission Control Module (Ignition On) 0.8
B13 Ignition Coil Cyl. No. 2 .1
B14 Ignition Coil Cyl. No. 3 .1
B15 Power Supply Fuel Tank Pressure Sensor 5
B16-B17 N/A N/A
B18 Vehicle Speed Sensor Signal (Ignition On & Drive Wheel Turning) Zero Or Battery (Fluctuates)
B19 EVAP Canister Shut-Off Valve (Ignition On) Battery
B20 Throttle Position Sensor Signal (Ignition On & Closed Throttle) 0.5
" Throttle Position Sensor Signal (Ignition On & Wide Open Throttle) 4.5
B21 Tachometer Signal (Ignition On) Battery
B22 N/A N/A
B23 Engine Coolant Temperature Sensor Signal (Ignition On & Closed Throttle) (12)
B24 PNP Idle Compensation Signal (Ignition On, In Park Or Neutral) Battery
" PNP Idle Compensation Signal (Ignition On, Except In Park Or Neutral) .1
B25 A/C Request From Climate Control (Ignition On) Battery
B26 Malfunction Indicator Light Operation Request Signal (Ignition On) 0-1
B27 N/A N/A
B28 Sensor Signal Ground (Ignition On) Zero
B29 A/C Pressure Sensor Power Supply (Ignition On) 5
B30 N/A N/A
B31 Fuel Tank Pressure Sensor Signal (Ignition On) .6-4.7
B32 Accelerometer Sensor Signal (Ignition On) 2.5
B33 N/A N/A
B34 Ignition Coil Cyl. No. 6 .1
B35 Ignition Coil Cyl. No. 4 .1
B36 Diagnostic Test Lead (Ignition On) 10-11
B37 N/A N/A
B38 PAIR Pump Relay Control Relay Battery
B39 N/A N/A
B40 A/C Relay Control Signal (Ignition On) 9
B41-B43 N/A N/A
(1) Check pin value between specified terminal and ECM terminal A42 (ground) if testing ECM "A" connector, or terminal B28 (ground) if testing ECM "B" connector.
(2) Injector ON time is 2.2-3.6 milliseconds. ON time increases with engine speed and load.
(3) 25 percent duty cycle. Duty cycle increases with engine load.
(4) Specification is 21-32 percent duty cycle. Duty cycle increases with engine speed and load.
(5) A/C voltage.
(6) Specification is 75 percent duty cycle.
(7) Specification is 68-89 percent duty cycle. Duty cycle increases with engine speed and load.
(8) Voltage is 1.3 volts with sensor temperature at 86°F (30°C) or 1.96 volt with sensor temperature at 212°F (100°C).
(9) Measured with negative lead connected to terminal A19.
(10) Zero-33 percent duty cycle.
(11) Measured with negative lead connected to negative battery terminal.
(12) Specification is measured in Hertz (Hz). Specification is 40 Hz with sensor temperature at 68°F (20°C) or 21.2 Hz with sensor temperature at 212°F (100°C).
(13) Specification is one volt at 85 psi, 2.2 volts at 203 psi, 2.8 volts at 261 psi, and 3.7 volts at 348 psi.
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